Replace a single dash with a double dash for options that have more
than a single letter.
llvm-bolt-wrapper.py has special treatment for output options such as
"-o" and "-w" causing issues when a single dash is used, e.g. for
"-write-dwp". The wrapper can be fixed as well, but using a double dash
has other advantages as well.
Reviewed By: rafauler
Differential Revision: https://reviews.llvm.org/D127538
Align with an upstream change D120305 to make PIE the default on linux-gnu.
Add `-no-pie` to tests that require it.
Reviewed By: maksfb, yota9
Differential Revision: https://reviews.llvm.org/D123329
Maksim Panchenko